Alarm signaling apparatus employing public utility circuits



K. L. BELL Oct. 26, 1943.

ALARM SIGNALING APPARATUS EMPLOYING PUBLIC UTILITY CIRCUITS Filed March 8, 1941 2 Sheets-Sheet l K. L. BELL Oct. 26, 1943.

ALARM SIGNALING APPARATUS EMPLOYING PUBLIC UTILITY CIRCUITS Filed March 8, 1941 2 Sheets$heet 2 Patented oct'zs, 1943 M SIGNALING APPARATUS EMPLOY- ING PUBLIC UTILITY CIRCUITS Keith Lansing Bell, Washington, D. 0., assignor of one-half to Curtis E. McGhee, Washingtp Application March 8, 1941, Serial No. 382,435

8 Claim.

This inventionrelates to signaling apparatus generally. More particularly this invention relates to signaling apparatus adapted to transmit burglar and fire alarms over telephone or electric lighting lines.

An object of this invention is to provide a burglar alarm for transmitting a signal over telephone or electric lighting lines to a central station, said burglar alarm consisting of a reproducing device controlled by a manual or automatic switch for transmitting an identifying signal giving the location and identification of the origin of said signal.

Another object of this invention is to provide signaling apparatus for transmitting a burglar or a fire alarm over existing public service lines, whereby the location of the burglary or fire may be immediatelymade known at a central station connected to said public service line.

A further object of this invention is to provide a signaling apparatus adapted to be used for signaling fire or burglar alarms over existing public service telephone or light lines, said apparatus being constructed to receive the power for the energization thereof from said lines.

Still a further object of this invention is to provide an apparatus for reproducing a recorded message and impressing said recorded message upon a telephone or a light circuit in a substantially silent and noiseless manner.

Another object of this invention is to provide a signaling device for signaling over existing public service lines or over a radio transmitter for the purpose of giving the location of a, fire or a burglary, the message consisting of the location of the fire or burglary being recorded, and said record being adapted to be reproduced after the transmission of predetermined signaling impulses.

Other and further objects of this invention will be apparent to those skilled in the art to which it relates from the following specification and claims. 4

In accordance with this invention, I provide a signaling system adapted to be connected to existing telephone, lighting or other public service lines, for the purpose of transmitting the location of a fire or burglary to a central station with the least possible delay. One of the features of my invention is that the apparatus thereof may be easily and readily installed, is extremely compact and silent in operation, and, furthermore, is adapted to be energized by power obtained from the telephone circuit or from the employs a recorded message consisting of the identity of the place where the apparatus is installed, namely, the business premises address thereof, and means for reproducing, amplifying, and impressing this message upon the telephone, lighting or other lines. This apparatus is placed into operation either by a manual or an automatic switch. For example, the apparatus may be installed adjacent to'the cash register of a store or other place to be protected, and a control switch may be placed next to the cash register so that if burglars enter the store'the operator may step on the switch control and immediately set the apparatus into operation to transmit a signal over the telephone circuit, warning the operator at headquarters that that particular store is being burglarized. Before the location of the store is transmitted, a noveldialing device transmits a plurality of impulses connecting the apparatus at the store or business premises with the special operator in charge of calls of this nature. This special operator immediately obtains a connection with the nearest police station and informs this police station that the store at the given location is being held up. Simultaneously, as the apparatus at the particular store or businessv premises is transmitting the location of the store ,tothe telephone operator, it may also transmit a radio signal upon a predetermined frequency giving the location of the store being held up. The frequency employed is preferably selected as the same frequency as that to which all of the scout cars of the police department are adjusted, so that all of these scout cars are immediately informed that a store at a given location is undergoing a robbery.

Further details of my invention will be apparent from the following specification, claims, and the drawings in which, briefly:

Fig. 1 is a schematic diagram of connections showing the apparatus of my invention connected to an electric lighting circuit;

Fig. 2 is a schematic diagram of connections showing the signaling apparatus of my. invention connected to a telephone circuit;

Fig. 3 is a detailed diagram of a form of thermostat that may be employed in controlling the apparatus of Figs. 1 and 2; and,

Fig. 4 is a detailed diagram showing features of the automatic dial employed in the apparatus shown in Fig. 2. I

Fig. 5 shows in a modified form of my apparatus a spring motor for driving the magnetic lighting'circuit The apparatus'of my invention record tape, and

Fig. 6 shows a detail of the foot-operated switch reference numerals I and 2 designate electric lighting lines such as normally carry the 110 volt power for residential lighting purposes from a central station C1 to a plurality of consumer's stations S1, S2, 82. Each of the consumer's stations S1, Si, Si, including an oscillation generator 3, consisting of a vacuum tube 4 and oscillatory circuits and 6, is connectedto the lines I and 2 by means of the coupling condensers 1 and 8, respectively. The oscillatory circuits 5 and 9 are coupled together, and one of these circuits, namely, circuit 5, is connected to the plate of tube 4, and the other of these circuits, namely, circuit 6, is connected to the grid of said tube. A modulating tube 9 having its grid and cathode connected to the pick-up coils III operatively associated with the magnetic record tape I I, is connected with its plate to the circuit 5, and to the choke I2, said choke being connected to the positive terminal of the rectifier I3. The cathodes of tubes 4 and 9 are connected together and to the negative terminal of the rectifier I3. The rectifier I3 consists of a transformer I4, having its primary winding connected to lines I and 2, and a rectifier tube I5 connected to suitable low and high voltage windings of the transformer i i, The output of the rectifier I3 is filtered by means of the filter III, which consists of one or more filter condensers and a choke coil or resistance.

A motor H for driving the reel I8 of the magnetic wire or tape II is connected in parallel with the winding of the. transformer I4 to' be energized from the lines .I and 2. Both the transformer I4 and the motor I! are connected to be controlled by the control switch I9, said control switch I9 may be either in the form of a manual switch, a thermostatic switch, or a door or window operated switch, or one or more of the aforesaid-switches in parallel.

The apparatus shown in Fig. 1 may be installed in various convenient locations where it is desired to detect burglaries or fires. For example, a number of switches, such as the switches I9 may be placed around a window or a door, or a plurality of these switches in the form of thermostats may be placed at various locations in rooms or buildings, so that if any one of these switches is actuated a fire or burglar alarm will be immediately transmitted over the lines I and 2. This alarm will be transmitted as soon as the switch I9 is closed and the transformer I4 and motor II are energized. The motor I1 may be either an electrical device or a mechanical device, such as a spring tension motor. If a spring tension motor II! is employed, then a solenoid H8 is connected in placeof the motor IT, as shown in Fig. 5, and this solenoid II8 releases the spring tension motor as soon as it is energized by pulling the rod I carrying the solenoid core down against the action of spring I2I and thereby disengaging the end I32 of rod I20 from the stop pin I2I carried on the drum II'I housing spiral spring H5. The terminals I and I3I of solenoid II8 are connected like the terminals of the motor I! of Fig. 1 across the primary of transformer I4 and hence are under the control of switch I9 of Fig. 1. The spring drum II'I drives through reducing gear wheel I28, the shaft I29 which in turn drives reel I8. When released, the motor tums the reel I8 to start the reproduction of the message recorded on the magnetic tape II. The pick-up coils III, III, are positioned adjacent to the magnetic tape I I, and pick up the message recorded on this magnetic tape and impress it upon the input of amplifying and modulating tube 9. The oscillations generated by the tube 4 are of relatively high frequency and are modulated by the amplifier modulator 9, which has its plate connected to the choke I2 and the plate circuit of the oscillator tube 4.

In Fig. 2 I have illustrated a form of this invention particularly adapted for signaling over existing telephone lines designated as lines solenoid 30.

20 and 2i leading to subscribers stations S4, St, $5, from a central exchange office C2 which comprises machine switching unit X. Across these lines at subscri'bers station S4 is connected an automatic dial 22 in series with the secondary of the audio frequency transformer 23. The automatic dial 22 is shown in detail in Fig. 4, and consists of a circuit make and break device 24, a dialing'tone selection segment 25, ten impulse-producing segments 26, and a circuit-closing segment 21. The dial 22 is also provided with a holding pin 28 associated with the solenoid operated catch 29. This solenoid operated catch 29 is attached to the armature of the The solenoid 39 is provided with a terminal connected to the switch 3I, which corresponds to the switch I9 of Fig. 1, and may work by a manually controlled switch, a thermometer controlled switch, or a window or door operated switch. In cases where this apparatus is installed for operation by operators adjacent to the cash register or cashier's window, this switch is a foot-operated device, as shown in Fig. 6. In Fig. 6, the switch means between line 20 and solenoid 30 comprises the contacts I51, I58, the former of which is carried on rod I54 which is normally urged upwardly by spring I56, and is engaged and depressed by foot-operated treadle I5I.

One side of the switch 3I is connected to the line 20 which is connected to the positive terminal of a suitable source of current supply located at the telephone central ofiice C2. The other side of the switch is connected to the solenoid 30 and to one terminal of the primary winding of the transformer, to one terminal of the voltage reducing resistor 32, and to one terminal of the reel driving motor 33. The other terminal of the solenoid 30 is grounded and through ground is connected to a negative terminal of the direct current source of supply located at the telephone central ofiice C2. Thus, when the switch 3I is closed either manually or automatically as the case may be, the solenoid 30 is energized from the direct current source of supply provided at the telephone omce, central or exchange. Other suitable conventional sources of energy for solenoid 30 and motor 33 may be provided.

When the switch 3I is closed and the solenoid 30 is energized, the catch 29 is disengaged from the pin 28, and the spring tensioned dial is released. The'dial thereupon rotates in the direction indicated by the arrow, and the segment 25 engages the switch 24 s that the secondary of the transformer 23 is connected across the lines 20 and 2|. This switch 24 is closed for an interval of time sufiicient in length to obtain the dialing tone. After the dial 22 rotates past the segment 25, the segments 26, which are shown as ten in number, operate to transmit ten impulses over the lines 20 and 2I for the purpose through suitable known automatic impulse train actuated machine switching equipmentunit x company. When the dial 22 is set into rotation the pin 28 is released by the catch 29. However, as this dial rotates, this pin 28 engages the manually operated catch 36, and the dial cannot be reset until this manually operated catch is released.

After the dial 22 passes the impulse segments 26 and comes to rest on holding segment 21, engaging the switch 24, the amplifier 34 is connected to the lines 20 and 2| ready for the reproduction of the message recorded on the magnetic tape 36. This magnetic tape 36 is rotated by the motor 33 between the magnetic pick-up devices 31, 31, which are connected to the grid and cathode of the amplifier 34. The message reproduced then from this magnetic tape is impressed upon the primary winding of the transformer 23 which is connected to the plate of the amplifier 34. The plate circuit of this amplifier is energized from the same direct current supplyas is employed for energizing the solenoid 36 and the motor 33. Likewise the filament of this amplifier tube 34 is also energized from this direct current supply in series with a voltage-reducing resistor 32.

In Fig. 3 I have illustrated a form of thermostat switch that may be employed as the switch l9 shown in Fig. 1 and the switch 3| shown in Fig. 2. This thermostat consists of a tube 38 of glass or other insulation material having a bulb 39 at the lower end thereof filled with mercury. Said bulb 39 is provided. with fins 40 of iron or similar material for more efiiciently transmitting heat into the mercury in said bulb. Said bulb may be made of iron if desired and it may be attached to a glass tube 38. This glass tube 38 is provided with a plurality of contacts 4| imbedded therein. The contacts 4| of the thermostat 38 are spaced so that this thermostat will operate at different temperatures, the lowermost contact operating at the lowest temperature and the upper contact operating at the higher temperature to close the circuit thereof. These contacts may be separated to give circuit control at different temperatures, for example, the lower contact may be arranged to function at 100 degrees F. and the upper one at 130 degrees F. with the intervening-contacts at temperatures between these limits. Other temperatures may be selected as desired.

On a non-dial telephone system the solenoid 30 may be replaced by a circuit closing device which maintains a closed circuit which automatically rings the central telephone operator who plugs in and receives the recorded message reproduced from the tape 36. This tape may be so arranged that it will be reproduced repeatedly for any given length of time. On rural telephone party lines where the telephone central operator is rung manually a suitable mechanically powered ringing device is employed. This is automatically recorded message from the tape 36. In this case the tape may again be reproduced repeatedly for any given length of time. The reproduced message is received by the central operator who paratus may through the use of the conventional telephone apparatus talk directly to the operator at the central station when the dial 22 is positioned to close the switch 24 through the operation of the segment 21.

What I claim is as follows:

1. In an alarm signaling system, a central station, a service station remote from said central station, a service distribution circuit connecting said central station and said service station, signal means at said service station for controllably applying a voice signal voltage to said circuit, said signal means comprising a repeating voice record means and pick-up means for converting said record into an electric current, and emergency control switching means adapted when actuated to energize said signal means so comprising said repeating voice record means and said pick-up means for applying voice signal voltage to said circuit.

2. A system according to claim 1, said circuit being normaly electrically energized, and said switching means being connected to said circuit for deriving energy therefrom for controllably energizing said signal means.

tion for controllably applying a modulated radiofrequency voltage to said circuit, said signal means comprising a radio-frequency oscillator having its output in electrical relation with said circuit, and modulating means connected to said oscillator and comprising a repeating voice rec- 0rd means and pick-up means for converting said record into an electric current, and emergency control switching means adapted when actuated to energize said oscillator and said modulatmg means and said repeating voice record means and said pick-up means for applying voice modulated radio-frequency current to said circuit.

4. A system according to claim 3, said circuit being normally electrically energized, and said switching means being connected to said circuit for deriving energy therefrom for energizing said oscillator and said modulating means and said pick-up means. a 4

5. In an alarm signaling system, a central station, a service station remote from said central station, a service distribution circuit connecting said central station and said service station, dialing means at said service station connected to said circuit and comprising a series of contact segments adapted to transmit a train of code switching impulses, voice signal means at said service station for controllably applying a voice signal voltage to said circuit, said voice signal means comprising a repeating voice record means and pick-up meansfor converting said record into an electric current, connections for applying said voice signal voltage to said circuit, and emergency control switching means adapted when actuated to release said dialing means for operation to transmit its code switching impulses and to energize said signal means for applying voice signal voltage to said circuit.

6. In an alarm signaling system, a central station, a service station remote from said central station, a service distribution circuit connecting said central station and said service station, dialing means at said service station connected to said circuit and comprising a series of contact segments adapted to transmit a train of code switching impulses followed by a continuous closed connection, signal means at said service station comprising a circuit element connected in series between said dialing means and said circuit and adapted to apply to said circuit element and said circuit a voice signal voltage, said voice signal means comprising a repeating voice record means and pick-up means for convertv ing said record into an electric current, and emergency control switching means adapted when actuated to release said dialing means for actuation of its code switching impulses followed by its continuous closed connection and to energlze said signal means for applying voice signal voltage to said circuit through said continuous closed connection.

7. A system according to claim 6, and manually operable locking and re-setting means adapted to lock said dialing means after it has transmitted said code switching impulses followed by said continuous closed connection.

8. A system according to claim 5, and solenoid means connected to said control switching means and adapted to release said dialing means into actuation, said circuit being normally electrically energized and said switching means being connected to said circuit for deriving energy therefrom for energizing said signal means and causing said solenoid to release said dialing means into actuation.

KEITH LANSING BELL. 

